This invention relates to the process of reducing vehicle tires and the like to small parts and more particularly to the method of and apparatus for cutting the tires into slices by the scissors-like action of a plurality of overlapping discs.
The number of used vehicle tires which must be disposed of in the United States each year is obviously very large. Tires cannot be burned because of the air pollution problems involved and attempts to dispose of such tires in conventional dumps have been unsatisfactory because of the nature and conformation of the tires which causes them to work to the surface. The tires tend to have a lower density than the soil in which they are buried, particularly in view of the fact that it is difficult to fill the interior of the tire in the course of normal burying techniques. This, coupled with the resilience of the tire body, causes it to slowly rise with respect to the soil, eventually emerging to the surface where it will interfere with normal surface usage of the land.
In addition, the tires deteriorate at a very slow rate and resist the usual plowing and harrowing techniques used to break up and intermingle other cast-off objects with the soil in which they are buried to speed deterioration. Obviously, if the tires are reduced to smaller sized parts, such parts could be more effectively buried and the deterioration process would be accelerated. It is, of course, necessary to reduce the tires to small parts in order to practice known reclamation process for the re-use of the natural or synthetic materials of which the tires are made.
The use of various reinforcing materials, such as wires or plastic fibers in fabricating tires has complicated the problems involved in reducing tires to smaller parts. Thus, apparatus of the type disclosed in U.S. Pat. No. 2,462,692 in which the tires are torn into small pieces by hook-shaped teeth is ineffective, at least with respect to modern tires, because the reinforcing materials will tend to clog the apparatus tending to require frequent maintenance and excessive power in operation. In addition, such apparatus is complicated to fabricate and maintain.
Apparatus of the type disclosed in U.S. Pat. No. 3,578,252 in which materials are subjected to the chopping action of rotary blades while supported on stationary cutter bars might be capable of cutting the reinforcing materials of modern tires but, due to the resilience of the natural or synthetic rubber comprising the main portion of the tire body, it cannot be effectively cut by such chopping action and will tend to clog the apparatus, thus requiring excessive power in operation. In addition, such apparatus tends to produce excessive vibrations and cannot be operated at high speeds.
Apparatus of the type disclosed in U.S. Pat. No. 3,656,697 in which the tires are ground into small particles by a plurality of rows of interfitting abrading rotary blades is capable of handling both the resilient material and the reinforcing material of modern tires but is inherently slow in operation at practical power levels. It will be understood that the danger of fire due to the heat produced in the grinding operation also limits the speed with which a given tire can be reduced to small particles in such apparatus even where a water spray is used.
It is an object of this invention to provide a method capable of cutting modern reinforced vehicle tires and the like into small parts in large volume at practical power levels.
It is a further object of this invention to provide apparatus capable of cutting modern reinforced vehicle tires and the like into small parts, which apparatus is simple and convenient to fabricate and maintain.
It is a still further object of the invention to provide a method and apparatus for cutting vehicle tires and the like into small parts in large volume, which apparatus may be transported to and the method practiced at remote sites.
It is yet another object of this invention to provide apparatus capable of cutting modern reinforced vehicle tires and the like into small parts, which apparatus does not produce appreciable heat or appreciable vibration in operation even at high volume.